Palaeolimnological study of the history of Loe Pool, Helston, and its catchment
The study traces the history and development of Loe Pool, a
50 hectare freshwater coastal lake near Helston, Cornwall.
using a wide variety of palaeolimnological and associated
research techniques. The principle upon which such research
is based is that there is an intimate relationship between
the history of a catchment and the lake into which it drains.
In addition, the history of the shingle bar which now
isolates Loe Pool from the sea is explored, as this has also
had a significant bearing on the lake's physical and
The study uses a combination of lines of evidence to
interpret the development of the lake-catchment system.
Palaeolimnological techniques. employed include the
examination of the physical nature of the lake sediments
themselves, and chemical and biological analyses, in
particular for sub-fossil diatoms. These are used to
establish both a chronology of sediment deposition, and also
a detailed history of the principal ecological changes
experienced by the Pool. In addition, a considerable amount
of historical documentary and cartographic 'material is
incorporated in the study, in order to provide corroborative
evidence of the major events that have taken place in the
history of the lake and catchment.
The results highlight the main influences on the lake, and in
particular, those of the last two hundred years. Marine
incursions dominated the lake's history up until the late
19th century, when both natural overspill of lake water and
the customary practise by local residents of 'breaching the
bar' ceased. Tin mining within the catchment has also had a
major impact on the lake and has given rise to several
periods of very rapid sediment accumulation, the most
significant of which took place in the 1930's and 1930's.
Following the cessation, in 1939, of all mining activity
within the catchment, the discharge of treated sewage
effluent, which had begun in 1930, became the dominant
influence upon the lake's ecology.
It is hoped that such an historical background will allow a
more sympathetic management of the lake in future years.